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Abstract:

A clamp grip for a container transport system including rare earth
permanent magnets encapsulated in non-magnetic material such as high
quality steel. Flexible positioning of the magnets allow for adapting to
varied design specifications. A rotatable control cam or cams may be used
to adjust grip arms between a grip and a release position. Air gap
distances between permanent magnets may be designed to maximize repelling
force to assist in the functioning of clamp grip mechanism.

Claims:

1. Clamp grip (K1, K2) for a container transport system, particularly for
a bottle transport system, comprising two grip arms (7) which can be
swiveled about one or about two axles (5) between a grip position and a
release position, the two grip arms (7) being applied with springiness in
the direction toward the grip position or toward the release position by
means of a force storing unit, and the force storing unit presents at
least one pair of mutually repelling permanent magnets (P1, P2).

3. Clamp grip according to claim 1, wherein each permanent magnet (P1, P2)
is encapsulated in a nonmagnetic material.

4. Clamp grip according to claim 1, wherein the permanent magnets (P1, P2)
of the pair are arranged directly on the grip arms (7).

5. Clamp grip according to claim 1, wherein the permanent magnets (P1, P2)
of the pair are attached to a rigid extension (7b) of the grip arms (7).

6. Clamp grip according to claim 1, wherein the clamp grip (K1) is
uncontrolled and can be pressed in each case against the repelling force
(F1, F2), which acts in the direction towards the grip position, between
the permanent magnets (P1, P2) of the container (B) which is to be
gripped or released, in that each grip arm (7) can be swiveled on a
support plate (4) about its own axle (5), and comprises an extension (7b)
which extends beyond the axle (5), and in that each permanent magnet (P1,
P2) is arranged in the end area of the extension (7b).

7. Clamp grip according to claim 6, and wherein flatly shaped repelling
surfaces (A) of the permanent magnets (P1, P2) of the pair are
substantially parallel to each other in the grip position, and, in the
release position, they are approached to each other to a maximum.

8. Clamp grip according to claim 3, wherein the permanent magnet (P1, P2)
has a cylindrical shape and it is accommodated in a capsule housing (12),
is the capsule housing (12) being fixed to the grip arm (7) and
comprising a can (14) with a thin-walled can bottom (15), facing the
repelling surface (A) of the permanent magnet (P1, P2), and a
thick-walled cover (16), which is applied to the open can end.

9. Clamp grip according to claim 8, and a filling body (17) inserted
between the cover (16) and the permanent magnets (P1, P2).

10. Clamp grip according to claim 6, wherein the extension (7b) is offset
at a slant with respect to the grip arm (7), in such a way that the
capsule housing (12) is positioned one of beneath the bottom side of the
grip arms (7), or beneath the top side of the support plate (4).

11. Clamp grip according to Claim 1, wherein the clamp grip (K2) is
controlled by a control cam which can be rotated between the extensions
(7b) of the grip arms (7) which can be swiveled about separate axles (5)
on a support plate (4), and can be held by the repelling force (F1, F2,
F3), which acts in the direction towards the release position, between
the permanent magnets (P1, P2), which are arranged on the grip arms (7)
between the grip areas (9) and the axles (5), with the extensions (7b) in
contact with the control cam (21).

12. Clamp grip according to claim 11, wherein each permanent magnet (P1,
P2) is cylindrical and accommodated in a capsule housing (12), which sits
with a retaining foot (18) in a recess (19) on the inner side of the grip
arms (7).

13. Clamp grip according to claim 12, wherein the retaining foot (18) is
arranged adjustably in the recess (19).

14. Clamp grip according to claim 11, wherein, in the container grip
position, a first air gap (L1) is provided between the permanent magnets
(P1, P2), and in that, in an extreme closed position of the clamp grip
(K2), if there is no container (B), a second air gap (L2), which is
smaller than the first air gap (L1), is provided between the permanent
magnets (P1, P2).

15. Clamp grip according to claim 11, wherein on of compensation pressure
spring pads (24), compensation leaf spring elements (23), or a
combination thereof are provided between the extension (7b) and the
control cam (21).

16. Clamp grip according to claim 1, wherein the force storing unit formed
by the permanent magnets (P1, P2) acts directly between the grip arms
(7).

17. Clamp grip according to claim 1, where one a grip arm (7) is attached
in a manner so it can be swiveled and the other grip arm (7) is fixed to
a support structure (1).

18. Clamp grip according to claim 17, wherein at least one permanent
magnet P1, P2) is fixed to the support structure (1).

19. Clamp grip according to claim 2, wherein the rare earths comprise
chemical elements of the third group of the periodic table of elements.

20. Clamp grip according to claim 2, wherein the rare earths are
lanthanides.

21. Clamp grip according to claim 2, wherein the rare earths are selected
from the group consisting of neodymium, samarium, and a combination
thereof.

22. Clamp grip according to claim 3, wherein the nonmagnetic material is
steel.

23. Clamp grip according to claim 22, wherein the steel is high quality
steel.

24. Clamp grip according to claim 4, wherein the permanent magnets (P1,
P2) of the pair are arranged approximately in the center between the grip
area (9) and the axle (5).

25. Clamp grip according to claim 5, wherein the permanent magnets (P1,
P2) are attached in such a way that the axle (5) is approximately in the
center between the grip area (9) and the permanent magnets (P1, P2).

26. Clamp grip according to claim 7, wherein in the grip position the
repelling surfaces (A) enclose an angle which opens in the direction away
from the axle.

27. Clamp grip according to claim 26, wherein the grip position angle is
smaller than 20.degree..

28. Clamp grip according to claim 7, wherein in the release position the
repelling surfaces (A) enclose an acute angle which is open in the
direction toward the axles.

29. Clamp grip according to claim 28, wherein the release position angle
is greater than 20.degree..

30. Clamp grip according to claim 29, and wherein the repelling surfaces
are brought in contact.

31. Clamp grip according to claim 8, wherein the cover is welded into the
open can end.

32. Clamp grip according to claim 12, wherein the retaining foot (18) sits
at the bottom of a recess (20) in the inner side of the grip arms (7).

[0002]The disclosure relates to a clamp grip for a container transport
system, such as a bottle transport system used in bottling operations.

BACKGROUND OF THE DISCLOSURE

[0003]Clamp grips that are controlled purely mechanically between the
release and the grip positions are known, for example, from EP 0 659 683
A. However, the cost of constructing the mechanical control is high.

[0004]From DE 297 13 510 U, mechanically controlled clamp grips are known,
and also uncontrolled clamp grips which are then actuated by the
containers themselves. The energy storage unit consists, for example, of
a spiral or screw compression spring which is actively used between the
grip arms. The uncontrolled clamp grip for bottles is opened by the
bottles to be gripped and moved to the clamp grip over inclined feeding
surface against the force of the energy storage unit, which acts in the
direction towards the grip position, and brought into the grip position
by the force of the energy storage unit. To remove the bottle, the latter
is pulled out of the closed clamp grip, and, in the process, it swivels
over the bevelled opening surfaces of the gripper arms against the force
of the spring loaded energy storage unit. Due to the force of the spring
storage device, the clamp grip automatically returns into the grip
position. The mechanically controlled clamp grip is reset in the
direction towards the force of the energy storage unit, for example, a
rubber spring, which force acts in the direction towards the release
position, by a rotatable control cam, into the grip position and back.

[0005]Container transport systems, particularly bottle transport systems,
must satisfy stringent requirements with regard to microbiological
conditions and cleaning; moreover, their operation must be reliable with
long service lives and very fast work cycles. Physical springs, such as
spiral springs or rubber springs or similar devices, which are positioned
in the vicinity of the grip area, i.e., close to the containers to be
gripped, are critical with a view to microbiology and cleaning, because
small soiling particles become easily deposited there, and, moreover,
they are frequently susceptible to aggressive cleaning media, which
shorten the service life of the spring which can be damaged mechanically
at any time, and break, with the result that the functional capacity of
the clamp grip is impaired or lost (high risk of damage to the
containers). In addition, during operation, abraded material or contents
may separate from the spring.

[0006]In the bottle transport technology it has already been proposed to
provide, in the case of controlled, multiple-compartment, articulated
clamp grips, a retention mechanism with mutually attracting permanent
magnets. Mutually attracting permanent magnets can be problematic
because, if they come in contact with, or extremely close to, each other,
an extremely strong force is required to loosen or separate them, which
can lead to an undesired snapping movement of the clamp grip and to
extremely high mechanical stress.

SUMMARY OF THE DISCLOSURE

[0007]The disclosure is based on the problem of providing an operationally
reliable, easily cleaned, controlled or uncontrolled, clamp grip which
satisfies the most stringent requirements from the microbiological
standpoint.

[0008]The mutually repelling permanent magnets in the energy storage unit
act as virtual springs without physical connection, where the spring
characteristic can be predetermined and optimized by the design of the
permanent magnets. The force is generated without any detectable abrupt
separation, i.e., when the permanent magnets move away from each other,
the repelling force decreases in accordance to the spring characteristic
from a maximum which corresponds to the maximum closeness between the
permanent magnets. This constitutes an optimal force characteristic for
clamp grips. The essential advantages of the virtual springs formed from
mutually repelling permanent magnets, in the case of a clamp grip,
however, are the rupture safety, the abrasion-free operation, the
possibility of preventing undercuts, angles or similar shapes, which
could promote the attachment of microorganisms or soiling, and the
insensitivity to aggressive cleaning media, combined with a minimal space
requirement. Cost effective permanent magnets are available in a great
variety of specifications and shapes with high production capacity, which
is important for clamp grips because a very large number of clamp grips,
for example, 300 or more, may be used in a container transport system.

[0009]To achieve a high production capacity with the smallest possible
volume, an optimized repelling force course, and still some repelling
force, albeit a weak one, even when the permanent magnets are separated,
it is advantageous for the permanent magnets to contain predominantly
rare earths, or to be manufactured from rare earths. For this purpose,
neodymium or samarium, for example, are advantageous, as are chemical
elements of the third group of the periodic table of elements, and
lanthanides. Such permanent magnets are characterized by a very high
power density per unit of surface or volume.

[0010]To eliminate deposition spaces for microorganisms and soiling
particles, and prevent detrimental influences of potentially aggressive
cleaning agents that are used at high pressure, it is advantageous to
encapsulate each permanent magnet in nonmagnetic material. For this
purpose, it is particularly advantageous to use high quality steel, which
can easily be kept free of microorganisms.

[0011]In an advantageous embodiment, the permanent magnets are arranged
directly on the grip arms, preferably approximately in the center,
between the given grip area and the axis of the grip arm. The permanent
magnets apply force to the grip arms moving them apart, and they open,
for example, the clamp grip with an initially very high and then
gradually decreasing repelling force. This repelling force acts
advantageously close to the grip area of the grip arms, i.e., close to
the gripped container. However, the position of the permanent magnets, as
well as their number, can be varied, in adaptation to the conditions,
such as the relative adjustment area of the grip arms, and similar
factors.

[0012]In another advantageous embodiment, the permanent magnets are
applied to rigid extensions of the grip arms, preferably in such a way
that the axis is located approximately in the center between the grip
area and the permanent magnets. In the process, a force is applied, for
example, to the grip arms by the repelling force in the direction towards
the grip position, and, in this way, the highest force is applied when
the clamp grips are open. Naturally, the position of the permanent
magnets in relation to the axis or the axes can also be chosen to be
different and adapted to the given operating circumstances.

[0013]In an advantageous embodiment of an uncontrolled clamp grip, which
is opened, for example, by the container itself, and whose grip arms
receive a force from the permanent magnets in the direction towards the
grip position, the permanent magnets are arranged on rigid extensions of
the grip arms.

[0014]In this case, an advantageous design can be one in which the just
formed repelling surfaces of the permanent magnets are substantially
parallel to each other in the grip position, i.e., at the time when the
action of the repelling force is weakest, whereas, in the grip position,
the surfaces are brought either as close as possible to each other, or in
mutual contact, i.e., at the time when the action of the repelling force
should be at a maximum. In the position with the lowest repelling force,
the repelling surfaces can also enclose a small acute angle, while a
reversed acute angle can be advantageous, in the position for the maximum
repelling force. This design ensures that the grip arms return as quickly
as possible to the grip position, as soon as the container, for example,
the neck of a bottle, is introduced into the grip area, or moved out of
it.

[0015]In principle, each permanent magnet can be advantageously
cylindrical, and be accommodated in a capsule housing.

[0016]The capsule housing is a can, for example, made of high quality
steel, with a thin can bottom, which faces the repelling surface of the
permanent magnet, while the open side of the can is closed by an
advantageously welded cover.

[0017]Between the cover and the permanent magnet, a filling disk can be
inserted, for example, to be able to use permanent magnets of different
size with one capsule housing size, or to protect the permanent magnet
from the welding heat during the welding of the cover.

[0018]The extension, on which the capsule housing is arranged, is
advantageously offset at a slant with respect to the grip arm, in such a
way that the capsule housing is positioned below the bottom side of the
grip arm, or below the upper side of the carrier plate, and interferes as
little as possible during the operation of the clamp grip.

[0019]In an additional advantageous embodiment of a mechanically
controlled clamp grip, a rotatable control cam acts between the
extensions of the grip arms, to adjust the grip arms back and forth
between the grip position and the release position. The repelling force
of the permanent magnets acts in the direction towards the release
position, and it keeps the extensions in contact with the control cam. In
this embodiment, the cylindrical permanent magnets can be accommodated in
capsule housings which are fixed with retaining feet in the grip arms. To
create a sufficient room for installation for the capsule housing, the
inner sides of the grip arms are provided advantageously with recesses

[0020]In this embodiment, it is advantageous if, in the container grip
position, a first air gap between the permanent magnets is provided, so
that they repel each other with near maximum repelling force. In
contrast, in the absence of a container, the clamp grip can be brought
into its extreme closed position, in which a second, but smaller, air gap
is provided between the permanent magnets and their capsule housings, and
thus the repelling force is highest.

[0021]To allow a better adaptation of the force action of the permanent
magnets to a given application case, it can be advantageous for the
retaining feet to be arranged adjustably in the recesses of the grip
arms.

[0022]To be able to use the clamp grips to grip the containers reliably,
in cases where the dimensions of the containers may present deviations,
it is advantageous to provide, between the extensions and the control
cam, compensation compression spring pads and/or compensation leaf spring
elements. The overall concept, as a result, has the advantage of forming
a springy prestressed system without tolerance movements in practically
any relative position of the grip arms.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023]Embodiments of the object of the disclosure are explained in
reference to the drawing. In the drawing:

[0033]The clamp grip K1 shown in FIGS. 1-3 is an uncontrolled clamp grip,
which is opened by the introduction and removal movement of a container,
which is not shown, and which assumes its grip position automatically,
without requiring any action on it from outside.

[0034]The clamp grip K1 is supported by a support structure 1 and an
optionally swivelable support 2 with an inclined bracket 3, on which a
support plate 4 sits. The clamp grip K1 presents two grip arms 7, which
are substantially mirror images of each other, and which, in this
embodiment, can be swiveled in opposite directions about two separate
axles 5, which are fixed, for example, with screws 6, and where the
swivel movement is substantially parallel to the plane of the top side of
the support plate 4.

[0035]Each grip arm has a front grip part 7a with a grip recess 9, a
front-side inclined introduction surface 8 and an inclined delivery
surface 10. The grip arms 7 are equipped past the axles 5 with rigid
extensions 7b. To the end area of each extension 7b, at least one
permanent magnet P1, P2 is attached, where the two permanent magnets P1,
P2, which work in cooperation with each other, are polarized in opposite
directions, so they repel each other. This means that the permanent
magnets P1, P2 face each other, for example, with their south poles, or
with their north poles. The permanent magnets are manufactured with the
predominant use of rare earths, and are very efficient. Such rare earths
are preferably neodymium or samarium, but may also include chemical
elements of the third group of the periodic table of elements, and
lanthanides. The permanent magnets advantageously present substantially
flat repelling surfaces A, between which a repelling force F1 or F2 is
generated, which varies as a function of the distance between the
repelling surfaces A. In the embodiment shown, the repelling force is
applied to the grip arms 7 in the direction towards the grip position in
FIG. 1, where the repelling force F2 has the maximum value if the clamp
grip K1 (FIG. 2) is in its release position. The permanent magnets P1, P2
are oriented towards each other in the swivel direction about the axles
5, and they can be arranged optionally so they can be adjusted along the
extension 7b.

[0036]In the grip position shown in FIG. 1, the repelling surfaces A are
substantially parallel to each other. In the release position shown in
FIG. 2, the repelling surfaces enclose an acute angle, which opens
towards the axles 5, and they are also in contact, as shown.

[0037]In an alternative embodiment, it is also possible to provide, along
each extension 7b, more than one permanent magnet P1 or P2, to pattern
the course of the repelling force in such a way that a considerable force
is still exerted even in the grip position in FIG. 1.

[0038]FIGS. 4-6 show a concrete embodiment of the upper gripper arm 7,
which is shown more schematically in FIG. 1. The grip arm 7 presents a
continuous bore 11 for the axle 5, and it is recessed adjacently to the
continuous bore 11. The extension 7b, for example, in the form of an
offset flat profile 13 is welded in this recess at 14. The permanent
magnet P1 is accommodated with hermetic seal in a capsule housing 12,
which, due to the offset of the extension 7b, can be located beneath the
bottom side of the grip arm 7 or beneath the top side of the support
plate 4 (FIG. 3), so that (see FIG. 3) no interfering or projecting parts
are present in the back area of the clamp grip, at the top.

[0039]The capsule housing 12 is, for example, a high quality steel can 14
with a thin-walled can bottom 15 and an open top side. The permanent
magnet P1 is, for example, in the shape of a cylinder with a flat
repelling side A and it is accommodated completely in the capsule housing
12. The open side of the top 14 is closed by a thick-walled high quality
steel cover 16, which may be welded, for example. A filling disk 17 can
be provided between the cover 16 and the permanent magnet P1.

[0040]FIG. 5 shows that the flat repelling side of the permanent magnet P1
is attached so it slants slightly upward, with the result that in the
closed position shown in FIG. 1, the two repelling surfaces A enclose a
small acute angle, for example, an angle of less than 20°, which
opens in the direction away from the axle 5.

[0041]FIGS. 7, 8 and 9 show top views of a mechanically controlled clamp
grip K2 in the release position (FIG. 7), in the container grip position
(FIG. 8), and in an extreme closed position (FIG. 9) without any
container B.

[0042]The clamp grip K2 again presents two grip arms 7, which are
substantially mirror images of each other, which are swivelable about the
axles 5, which are separate in this embodiment, in opposite directions,
and which present extensions 7b that extend beyond the axles 5. The clamp
grip K2 is controlled by a rotatable control cam 21, which can be turned
either back and forth, or continuously, by means of a drive cam 22, and
which operates between the inner sides of the extensions 7b. Between the
control cam 21 and the inner sides of the extensions 7b, leaf springs 23
are also provided, which are applied against the control cam 21, as well
as optionally pressure spring pads 24. The leaf springs 23 and/or the
pressure spring pads 24 confer to the drive system of the clamp grip K2
an intrinsic springiness and a permanent force transfer contact with the
control cam 21, and they compensate for any dimensional deviations among
the containers B to be gripped.

[0043]On the inner sides of the grip arms 7, between the grip areas 9 and
the axles 5, permanent magnets P1, P2, in pairs, are provided, and are
mutually repelling. Optionally, more than one pair of permanent magnets
P1, P2 can be provided.

[0044]Each permanent magnet P1, P2 is accommodated advantageously in the
capsule housing 12, which is fixed with a foot part 18 in a recess 19. To
be able to accommodate a large useful magnet volume, the inner sides of
the grip arms 7 are advantageously shaped with recesses 20. The foot
parts 18 can be adjusted optionally in the recesses 19.

[0045]In the release position shown in FIG. 7, the oval or elliptic
control cams 21 is in a turning position, in which the extensions 7b are
approached maximally to each other. The two permanent magnets P1, P2 are
apart from each other and they apply a force F1 to each other. In the
process, the flat surfaces of the permanent magnets P1, P2 enclose an
acute angle, which is open in the direction away from the axles 5.

[0046]In the container grip position of the clamp grip K2, which is shown
in FIG. 8, the control cam 21 is turned in such a way that it acts
substantially with its greatest dimension between the extensions 7b, and
slightly deforms the leaf springs 23 as well as the pressure spring pads
24, holding the container B with a predetermined grip force. The
permanent magnets P1, P2 are approached to each other, so that, between
them, there is an air gap L1 with a dimension, for example, y1, and a
relatively strong repelling force F2 is active. The two grip arms 7 are
approached to each other leaving only a slit separation x1.

[0047]In the extreme closed position of the clamp grip K2, which is shown
in FIG. 9, if there is no container B, the grip arms 7 are approached to
each other leaving only a slit separation x2, which is smaller than the
slit separation x1, and the two permanent magnets are also approached to
each other, leaving an air gap y2 which is smaller than the air gap y1.
The maximum repelling force F3 is applied.

[0048]In the embodiments shown, the grip arms 7 can also be attached so
they can be swiveled to a common axle. Furthermore, the repelling
surfaces A of the permanent magnets P1, P2 of each pair can optionally be
rounded to a convex shape to achieve a different characteristic course of
the repelling force. In the embodiment shown in FIGS. 7-9, the permanent
magnets P1 can also be embedded directly in the grip arms, assuming that
the material of the grip arms 7 is not magnetic, for example, high
quality steel. Furthermore, it is possible to attach only one grip arm 7
so it can be swivelled, and to fix the other arm to the support
structure.